The prior art accepts, generally, the Otto cycle and Diesel cycle internal combustion engines, the former being constant volume and the latter being constant pressure, in theory. The constant pressure concept is much to be desired but is available only in theory with engines that compress the full cylinder volume and inject a full measurement of fuel at or during travel of the piston-crank through the top dead center position. At the present state of the art, compression ignition engines, Diesels, are acknowledged to compress 40% excess air in order to establish auto ignition temperature at the top of the piston stroke, and although this has its benefits in providing more than adequate support for combustion, it has great disadvantages in the waste of energy provided for the compressive function and in the increased structural requirements of large volume high compression engines; and all of which involves inefficiency which entails friction and heat losses. Therefore, it is an object of this invention to provide an internal combustion heat engine of the cylinder and piston type wherein a substantial portion of the compression is restricted to low pressure for support of combustion, and wherein a limited portion of the compression is extended to high pressure for establishing auto ignition. With the concept herein disclosed, the aforementioned 40% excess air is reduced to a minimum and/or to a small excess, say for example 10 to 15% or less as may be desired; and the engine structure is commensurately reduced in heft with corresponding decrease in construction costs and with increases in efficiency.
The engine of the present invention is a departure from the Otto cycle in that auxiliary ignition means and an explosive power stroke are avoided, and is a departure from the Diesel cycle in that full volume compression and measured fuel injection at the beginning of the power stroke are avoided. Replacing the foregoing is controlled injection applied in a manner which identifies the present invention as a Compression Ignition Controlled Pressure Heat Engine. To this end it is an object of this invention to continuously inject fuel throughout the effective portion of the work stroke, at a controlled rate establishing burning pressures less than the pressure of the aforementioned storage air that is thereby releasable from the aforementioned storage chamber to support combustion within the cylinder.
An object of this invention is to advantageously employ the constant volume variable potency injectors as disclosed in U.S. Pat. No. 3,749,097 issued to me on July 31, 1973 and U.S. Pat. No. 3,921,599 issued to me on Nov. 25, 1975. It is by means of these fuel injectors, or like injectors, that controlled fuel burning and cylinder pressures are maintained below the stored combustion supporting air pressures. With this invention a constant volume pump intermixes two liquid and discriminately injects the admixture thereof discretely therefrom and into the engine cylinder at a controlled potency. The injector per se is characterized by its differential pump means which are advantageously employed to acquire structural strength and accurately metered fuel injection.